The following correction was printed in the Guardian's Corrections and clarifications column, Tuesday 2 February 2010

A list below of Cadbury's top-selling sweets went astray in including Fuse and Trebor Bassett. Fuse was discontinued in 2006, and Trebor ­Bassett is not a product in its own right.

Despite the billions of dollars changing hands, the political furore and the loss of one of the oldest names in British business, the question on many lips is simple: is it curtains for the Curly Wurly?

Kraft was doing all it could today to reassure consumers (among others) that it would respect Cadbury's heritage. But it also boasted that it would now own 40 confectionery brands with sales of more than $100m (£60m), underlining the fact that huge corporations tend to be in thrall to global products, perhaps casting doubt over the long-term future of some of the smaller Cadbury names.

Multinationals are also keen on stamping out local names in favour of those recognisable worldwide. Some of Britain's favourites have already been lost to global-speak. Opal Fruits became Starburst, Marathon became Snickers, and Treets became M&Ms.

Cadbury's top sellers, Dairy Milk, Trebor Bassett, Crunchie, Fuse and Flake are doubtless safe, but there are a number of brands that make up less than 0.1% of the company's sales in Britain. These include the Curly Wurly, Picnic and Caramilk, according to figures from Datamonitor. Dairy Milk has sales in Britain of £369m, according to marketing analysts Nielsen, while Turkish Delight has sales of just £15.8m. Neither is a brand safeguarded simply by being profitable. A decade ago, Unilever reduced its number of brands from 1,600 to 400 to focus on products that were No 1 or 2 in their market.

"There is a very real danger that some of the brands will disappear," said Tim Richardson, author of Sweets: a History of Temptation. "Whenever there is a big takeover, a company will look to improve productivity and ­profitability. Within five years, we could be looking at a Cadbury with far fewer brands. Mars only makes big brands, and Kraft might follow that route, which is very modern. Cadbury is not sentimental and will close underperforming lines, but you can't help thinking that without the same emotional investment in say, 'Finger of Fudge', the ­conversation in the Kraft boardroom will be very different."

It is unlikely though, he added, that Kraft would attempt to impose ­American-tasting chocolate. "You mess with ancient products at your peril. Remember what happened with New Coke – they quickly had Classic Coke."

Branding expert Graham Hales, managing director at Interbrand, believes Kraft will tread carefully. "Cadbury is part of the national fabric and Kraft will not want to undermine that. They understand how to manage brands, and they are not going to look to destroy the value of the business they have just bought."

But even if a brand is dropped it is no guarantee it will lie dormant for good. Cadbury discontinued Wispa in 2003 and reintroduced it in 2007 for a "limited" period after an internet campaign. Such was its success, that it once again became a permanent part of the Cadbury line-up.